Enum NodeKind 

pub enum NodeKind<S: WorkflowState = State, M: MergeStrategy<S> = StateMerge> {
    Task(TaskNode<S>),
    Condition(ConditionNode<S>),
    Barrier(BarrierNode<S>),
    Parallel(ParallelNode<S, M>),
    External(Arc<dyn FlowNode<S>>),
}

节点类型枚举。

泛型参数

• S — 类型化状态（默认 State = HashMap，向后兼容）
• M — 并行合并策略（仅 Parallel 变体使用，默认 StateMerge）

Variants

Task(TaskNode<S>)

自定义逻辑

Condition(ConditionNode<S>)

条件分支

Barrier(BarrierNode<S>)

Human-in-the-loop 审批屏障

Parallel(ParallelNode<S, M>)

并行执行多个分支

External(Arc<dyn FlowNode<S>>)

外部节点（由 lellm-agent 等 crate 提供）

Trait Implementations

impl<S: WorkflowState, M: MergeStrategy<S>> Clone for NodeKind<S, M>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<S: WorkflowState, M: MergeStrategy<S>> FlowNode<S> for NodeKind<S, M>

fn execute<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, ctx: &'life1 mut NodeContext<'life2, S>, ) -> Pin<Box<dyn Future<Output = Result<(), GraphError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

执行节点逻辑。